We
are developing carbon nanotube-modified
microelectrodes for in vivo sensors. Carbon nanotubes have
interesting electrical, chemical and mechanical properties.
In electrochemical research, the conductivity
of the tubes, a consequence of their electronic properties, has been
exploited
as a means of promoting electron transfer.
A variety of biologically-relevant, redox-active species have been
studied at carbon nanotube-modified electrodes including hydrogen
peroxide,
NADH, cytochrome C, dopamine, and proteins. While the use of
carbon nanotubes in
biosensors is promising, few studies have addressed the need for fast
detection
of biological molecules in order to follow the kinetics of biological
responses. Therefore, our aim is to
characterize detection of neurotransmitters at carbon nanotube-modified
electrodes with fast scan cyclic voltammetry.
Our hypothesis is that adding carbon nanotubes will increase the
electrode surface area, increasing the number of adsorption sites that
will
lead to greater sensitivity for adsorbed species. We have studied
various methods for fabricating nanotube electrodes, primarily
dip-coating CNTs onto carbon-fiber microelectrodes (CFMEs).
Further studies to create more aligned CNTs and fabricate CNT sensors
without CFMEs are underway.
Diagram of a single-walled nanotube.
